651 — Al-Hasan ibn al-Sabbāh related to me, from Abū Yazīd al-Raqqī, from Fudayl ibn Iyād—may Allah have mercy on him—who said: “Neither pilgrimage, frontier duty, nor jihad is more arduous than restraining the tongue. If you awoke preoccupied with your tongue, you would awake in deep anguish.”